Fix broken x-if element initialization

[calebporzio]

In the following snippet, before this PR, "foo" was never getting set to "baz". Now it is.

<div x-data="{ show: false, foo: 'bar' }">
    <h1 x-on:click="show = ! show"></h1>

    <template x-if="show">
        <h2 @click="foo = 'baz'"></h2>
    </template>

    <span x-text="foo"></span>
</div>